Modern digital photo cameras have a limited dynamic range capability, usually not being enough to capture all the details in a scene. The user therefore has to choose between a picture that has details in shadows but is overexposed and one that properly exposes highlights but is underexposed everywhere else. Capturing multiple images of the same scene at different exposure levels and combining them is currently the most common way to achieve a high dynamic range photograph. This offers best results for tripod mounted cameras and static scenes. Conventional display devices have a limited dynamic range and different tone-mapping techniques may be applied to compress the dynamic range of the HDR image, preserving certain relevant details.
Typically, combining two image captures with different exposures and content can tend to produce a high dynamic range (HDR) image with undesired ghosting artifacts, particularly when a handheld digital still camera or camera-phone is being used. Taking multiple exposures with a single aperture tends to lead to ghosting artifacts caused by moving objects in the scene between exposures. Usually by compressing the dynamic range using a tone-mapping technique the contrast of an image may be reduced, although some details are typically lost and the overall appearance intended by the camera's manufacturer is severely altered.